What would he look like? How powerfull would he be? all is answered.
Chapter: 1 Childhood!
Kaguya had just given birth to her first and only child, this childs name was "Itsuki Otsutsuki" He had a Purple rinnegan and a Blue tenseigan, she was shocked the child had such beautiful eyes. Ofcourse, Kaguya had her bad times with this child. Itsuki was often a prankster, but when serious can be a force to be reckoned with even at the age of 6, Itsuki almost beat his mother when she had went all-out. Kaguya was very suprised, she never thought anyone would have a chance to surpass her in power. Today was Itsuki's 10'th birthday a very important day, Itsuki had fallen in love with a human girl. His mother disagreed with it, but he ofcourse liked her and well as he says "Love is Power, Power is Love!" He wouldn't stop. But today that girl had to go to the 'Immortal Tree' as a 'Blessing' or more like a sacrifice. "Bye Hinata!" He said waving goodbye to her. He went to his pond and meditated and 'accidently' had forced himself to levitate and look over to the Immortal Tree. He had seen Hinata next to it when the tree sucked her in? He kept looking, after a couple of hours no-body came back so he decided to go over there. His mother told him to always stay away from their, and he was always wondering what happened there. He went inside the tree, and...found Hinata's dead body. Itsuki was outraged he knew he could revive her but he said 'She would like to rest, it is wrong to bring back the dead.' His eyes glew Blue and Purple and then that is how he found himself in this situation, fighting his mother, the rabbit goddess Kaguya. She had absorbed the Juubi and Itsuki was unsure he could defeat his mother, espeically with the Juubi inside her, he decided to wing it and he used his 'speical' jutsu. He quickly cast a genjutsu witch Kaguya, couldn't have broken out, suprisingly. He then tried to stab her but then he missed, Kaguya dodged. Somehow. Itsuki then used a Jutsu he created testing the Rinnegan and Tenseigan. Called "Almighty destruction, death's touch!" witch, well anything that touched the jutsu instantly died, except the caster.
Itsuki used a seal (A enhanced version of Hiraishin) To teleport behind Kaguya and he hit her to the ground. He stared at his dead mother, and the Juubi had tried to get out. But Itsuki took it inside himself. He looked around the world. Nothing he needed. He decided to have some children, Indra and Asura. Itsuki then cast a genjutsu on himself for him to be in slumber for 1000's of years. (Itsuki will wake up during World War/Clan wars.)